Wireless communication systems are widely deployed to provide various types of communication content, such as, voice, media, data, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth and transmit power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, 3GPP LTE systems, and orthogonal frequency division multiple access (OFDMA) systems.
Generally, a wireless multiple-access communication system can concurrently support communication for multiple wireless terminals. Each terminal communicates with one or more base stations via transmissions on forward and reverse links. The forward link (or downlink) refers to a communication link from base stations to terminals, and the reverse link (or uplink) refers to a communication link from terminals to base stations. This communication link may be established via one or more of single-in-single-out (SISO), multiple-in-single-out (MISO) or multiple-in-multiple-out (MIMO) systems.
A wireless communication system can also be employed to provide various types of services. These services include point-to-point services, or dedicated services such as voice and packet data, whereby data is transmitted from a transmission source (e.g., a base station) to a specific recipient terminal such as in cellular telephony or Internet communications. In addition to these services, several providers have launched mobile multimedia services closely resembling traditional broadcast services such as radio, television etc. Such services push content aggregated into channels to subscribers. In some cases, the content may be taken from, for example, existing TV channels or it may be other special content.
If the point-to-point model of communications is employed for such mobile multimedia services the content server that delivers content to the users must establish and maintain a separate point-to-point connection for each recipient. While this approach may be adequate for low to moderate number of subscribers it does not scale well as the number of subscribers increases. Thus, the characteristics and requirements for point to multipoint transmissions such as multimedia services or broadcast services are very different in many aspects from those for more dedicated services such as cellular telephony. For example, dedicated resources (e.g., physical channels) are allocated to individual terminals for dedicated services. In contrast, common resources may be allocated and used for all terminals expected to receive the broadcast services. Moreover, the transmission for a broadcast service would need to be controlled such that a large number of terminals with different individual attributes are able to reliably receive the service, while optimizing the resources required for implementing the service. Hence, techniques to implement such broadcast services efficiently in a wireless communication system need to be explored that allow reservation of bandwidth for broadcast services, operating flexibility depending on broadcast/multicast loads, fast switching time, and minimal wake up time for access terminals thus improving battery efficiency.